Carbon material has been used for negative electrode of lithium ion secondary cell, since the negative electrode composed of the carbon material is less likely to allow dendritic lithium to deposit thereon even after repetitive charge-discharge cycles, and safety may therefore be ensured.
For example, Patent Document 1 discloses a carbon material having a nitrogen content of 0.1 to 5% by weight, and a volume of pores, occupied by those having a pore size exceeding 0.33 nm, of 0.1 to 50 ml/kg.
Patent Document 2 discloses a carbon material obtained by carburizing a specific resin composition, and having a pore volume of 50 ml/kg or smaller.